I have four prewritten books stored as sub-items of a single book item class. The issue is referencing them in recipes and advancements.

This is the Advancement Json as it was in 1.12.2:

Spoiler

{
    "parent": "thejungle:junglestory/root",
    "display": {
        "icon": {
            "item": "thejungle:book_scale"
        },
        "title": {
            "translate": "advancements.junglestory.book_scale_i.title"
        },
        "description": {
            "translate": "advancements.junglestory.book_scale_i.description"
        },
        "show_toast": true,
        "announce_to_chat": true
    },
    "criteria": {
        "book_scale_i": {
            "trigger": "minecraft:inventory_changed",
            "conditions": {
                "items": [
                    {
                        "item": "thejungle:book_scale",
                        "data": 367
                        }
                    ]}}}
                }}

 

In 1.13.2 "data" causes an error reading "disallowed data tag".

The following is an extract from the book scale item class. There are four prewritten books in total:

Spoiler

		eastScale = new ItemStack(this);
		eastScale.setDamage(367);

		NBTTagCompound tag = new NBTTagCompound();
    	eastScale.setTag(tag);
	    		
		tag.setString("author", ("Salvestrom"));
		tag.setString("title", ("The Books of Scale: The Bringer"));//Lord of the Living"));
		NBTTagList bookPages = new NBTTagList();
		tag.setTag("pages", bookPages);
	    bookPages.add(new NBTTagString
	    		("\"Who really knows\n"
	    		+ " and who can swear\n"
[And so on…]

 

Initially I thought flattening wouldn't work since I would still need a sub item within each flattened book item class, but then I realised that each separate class would be sufficient for distinguishing them. However, if it's possible to resolve this by changing the word "data" to something else, that would be great!

Anyone got anything? Creating four separate classes for the book just seems wasteful…

Create 4 separate classes. Subitems are no longer a thing.

 

https://gist.github.com/williewillus/353c872bcf1a6ace9921189f6100d09a#whats-the-deal-with-metadata

You can still create sub-items, and successfully register them and use them in game. But there seems to be no way to distinguish them in a recipe file. But for separate classes does seem to be the only way forward. Seems odd to leave the sub item functionality in place.

Edit: and even if I use four separate classes, each prewritten book will have to be registered as a sub item still. It will resolve my issue with recipes, but it won't remove my use of subitems.

Edited July 23, 20196 yr by salvestrom

1 hour ago, salvestrom said:

You can still create sub-items, and successfully register them and use them in game. But there seems to be no way to distinguish them in a recipe file. But for separate classes does seem to be the only way forward. Seems odd to leave the sub item functionality in place.

Edit: and even if I use four separate classes, each prewritten book will have to be registered as a sub item still. It will resolve my issue with recipes, but it won't remove my use of subitems.

I'm not sure if you have solved this or not, but you need to create more than one instance of the item. Subitems are not standard anymore, and will probably be removed from existence. I assume the only reason something like subitems in creative tabs still exists is probably because what if you want to show two same energy items with different durability(energy values).

1 hour ago, Animefan8888 said:

I assume the only reason something like subitems in creative tabs still exists is probably because what if you want to show two same energy items with different durability(energy values).

Potions. And the method is called fillItemGroup.